I have it working fine towards AD (not sure it’s 2016, - maybe 2012 … but hopefully that shouldn’t matter)
Can you share your LDAP settings? - specifically User filter where I use (|(sAMAccountName={login})(mail={login})) <— it allows login with just username vs full email address
Also note I’ve seen from time to time that users had to enter credentials a few times before it worked … but never reported as a Metabase bug - because such a thing is super hard to repro i a reliable way. 
For comparison (I shared some early one’s here - now I run with SSL + have also recently )